The present invention relates to a propeller spinner for model airplanes, and particularly to such a spinner which is exceptionally easy to install and remove or dismount to gain access to the airplane propeller and the retaining means therefor.
Model airplanes, as well as various outboard marine assemblies, include a propeller on a propeller shaft, with the propeller being disposed between a thrust plate fixed to the propeller shaft and retaining means such as a propeller nut threaded onto the propeller shaft. In many model airplanes, the thrust plate is directly associated with the engine thereof. A streamlined spinner normally is employed over the propeller hub and the retaining means. The spinner is generally hollow for housing the propeller hub and retaining means, and is generally axially symmetrical for aerodynamic purposes. It is quite desirable for the spinner to be releasably mounted and readily removable for access to the propeller hub and its retaining means for servicing the same, for instance to tighten or replace the propeller.
Many attempts have been made to provide a propeller spinner which is easy to install and remove or dismount. For example, threaded connections have been used for joining the propeller spinner to the propller shaft and a special tool must be used to disassemble the propeller spinner. This is rather complicted and expensive and is not very desirable for servicing in the field. Other spinner assemblies utilize bolts or screws, some of which remain permanently in position on the spinner, again requiring tools for installing and removing the spinner in the field.
Still other prior devices employ a rigid disc mounted behind the propeller around essentially the entire circumference of which the spinner must be snapped or elastically engaged to make connection with the disc. This is an acceptable assembly but one which heretofore presents difficulty in positioning and as far as mounting and dismounting of the spinner are concerned. Often times the spinner is spontaneously released by a quick unsnapping action from the mounting disc, causing painful bruising to an operator's hands. With a more loose fit between the spinner and mounting disc, the spinner gradually loosens during operation and vibration of the airplane engine.
The present invention is directed to solving these problems by providing a new and improved spinner or spinner assembly which requires no bolts, screws, or other fastening means requiring the use of tools in the field and does not require any considerable force for removing the spinner from its mounting.